I have read some horror stories about aftermarket senders. I can put up with some inaccuracy as long as the gauge reads close when it gets to empty. In a perfect world the gauge would read E with a gallon or so left in the tank.
If it was just 1 gallon, I could live with that.
I suppose for some folks an advantage of a short arm is that they can show empty while there's still 2 to 4 gallons remaining.
I'd prefer the thing more accurate and not having to wonder if 1/2 on the gage means 8 gallons or 5, and especially what 1/4 means.